Sudoku again

I took 2 Sudoku puzzles in to M's small group yesterday (Friday) to work on after I finished reviewing area and perimeter with them. This time I made sure that I did them first, so I could check and correct the kids as they were working on them. Good thing! The 9x9 was supposed to be easy, but after working it, I knew it would be way too much for them, so I fiddled with it and added about 6 more numbers. Well, while I was working on this one, A came in and wanted to see what I was doing. So, I gave him the 6x6 I had for the 4th graders. I had to give him a couple of hints, but he did great on it. I was rather surprised, therefore, on Fri when several of M's classmates had a lot of trouble with the 6x6. I had to have them erase it several times, but in the end, I think they all finished that one. M and one girl finished their 9x9 and a few others were going well. I promised them I would bring in more for them next week - though I told them it would be for on their own - I'll bring something else for class time.